cobbpg

Unity hotswapping notes

Unity has built-in support for hotswapping, which is a huge productivity booster. This feature works not only with graphics assets like bitmaps and meshes, but also with code: if you edit the source and save it, the editor will save the state of the running game, compile and load the new code, then load the saved state and continue where it left off. Unfortunately, this feature is very easy to break, and most available 3rd party plugins have little regard for it.

It looks like there’s a lot of confusion about hotswapping in Unity, and many developers are not even aware of its existence – which is no wonder if their only experience is seeing lots of errors on the console when they forget to stop the game before recompiling... This document is an attempt to clear up some of this confusion.

Nota bene, I’m not a Unity developer, so everything below is based on blog posts and experimentation. Corrections are most welcome!

The basic flow of hotswapping

rickyah

using System;
using UnityEngine;

/// <summary>
///     This is a generic Singleton implementation for Monobehaviours.
///     Create a derived class where the type T is the script you want to "Singletonize"
///     Upon loading it will call DontDestroyOnLoad on the gameobject where this script is contained
///     so it persists upon scene changes.
/// </summary>
/// <remarks>

ashleydavis

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using UnityEngine;

/// <summary>
/// A simple free camera to be added to a Unity game object.
/// 
/// Keys:

shanecelis

/*
  CoroutineTests.cs -- Shane Celis

  I was curious about how one could manually drive Unity's coroutines
  without necessarily putting them into Unity's scheduler.  At the
  heart of it, it's really easy to manually drive them:

  // Get the coroutine.
  IEnumerator ienum = MyCoroutine(); 
  // Run it until it yields.